Aluminum stearate solutions and art of making the same



Patented Mar. 3, 1936 UNITED. STATES ALUMINUM 'STEARATE SOLUTIONS AND ART OF MAKING THE SAIVIE Jacob Dolid, Bridgeport, Conn.

No Drawing. Application March 14, 1930, Serial No. 435,952

14 Claims.

- their introduction into porous materials, such as textiles and natural and artificial stone building materials for the purpose of damp-proofing and weather-proofing them, has always been desirable.

' Heretofore, true solutions of aluminum soaps have been available in dilute concentrations which limit the amount of soap absorbed by the pores at an application. Another method of employing aluminum soap has been as a dispersion which introduces the soapinto' the pores in the form of fine particles. Still another method is the process of saturating the material to be waterproofed with a solution of an aluminum salt followed by treatment with a solution of sodium soap whereby aluminum soap is precipitated in the pores of the article. These methods mentioned suffer the disadvantages of either permitting the introduction of only a small amount of aluminum soap in the article to be waterproofed or in such a form as not to produce :1. continuous water-repellent film. I

True solutions of aluminum soaps'in volatile solvents are preferable as mediums for waterproofing porous substances, because on evaporation of the solvent, awater-repellent film is left behind in the pores or on the fibres.

The efiectivenes s, and efficiency for its purpose, of an aluminum soap waterproofing. solution, depends largely upon the degree of concentration of the solution-that is, the proportion of the aluminum soaps to the solvents or vehicle carrying the soaps. Solutions of high concentrations of aluminum soaps will naturally leave more water-repellent aluminum soaps, behind on evaporation than those of lower concentrations, and if the viscosity of concentrated solutions of aluminum soapscan be kept low, they will be just as penetrative as those of low concentration.

It is therefore apparent that the higher the degree of concentration of the aluminum soap solution and the lower its viscosity, the, more effectual will it be in waterproofing the material to which it is applied. I

Although approximately twenty years of research have been applied to this problem of making an aluminum soap of a high degree of concentration, the art, to the best of my'knowledge and belief, has been unable to'make an aluminum soap solution having a higher concentration than 12% which is suitable for use as a waterproofing material. v

The difilculty has been that the addition of a larger proportion of aluminum salts with rela- PATENT OFFICE;

tion to the solvent or vehicle in thesolution made the solution so much more viscousi.'e. so much less liquid, that it would not freely flow and penetrate the pores of the material being treated.

A salient feature of this invention is the provision of an aluminum'soap solution having a degree of concentration of upwards of 12% and which is sufiiciently liquid to be free-flowing "so as to penetrate the pores of the material being treated.

'While the production of aluminum soap solu-. tions of high concentrations is a salient feature of this invention, it is not the sole feature nor even the paramount feature, for; when m'adeflaccording to the present invention, any aluminum soap solution of any degree of concentration is more freely flowing, and thus has greater penetrating qualities than solutions of the same de-. gree of concentration as heretofore made. Further, the ease or facility with which the solutions.

are formed according to the present invention, is

a material and important feature thereof. The

ability to use cheap solvents of petroleum origin I is another distinct advantage.

In attacking theproblem, I found byexperiments, that aluminum soap solutions could be made as followsz-Assumirig that a solution of 15% concentration is desired, 3 parts of aluminum palmitate or stearate, i. e. aluminum soap, are mixed with 17 parts by weight of gasoline, benzol, toluol, or other hydrocarbon-solvent. The mixing may be done in any type of mixerl which will thoroughly mix the ingredients and.

the result of the mixing is the formation. of a gel,

for the addition of the solvent causes the alumi-,

num soap to swell andonly a very small proportion of aluminum soap is capable of being dissolved by the solvent to yield a freely-flowing solution.

To this gel is added a relatively small quantity of triethanolamine which I have found causes the gel to become liquefied, reducing the viscosity to a degree depending upon the amount of triethanolamine added to the mixture. In the proportions above given of 3 parts aluminum soap to 17 parts by weight of hydrocarbon-solvent, I have found that the addition of .2 parts of triethanolamine or less makes the solution sufiiciently freefiowing for use as a waterproofing material.

A higher degree of concentration than 15% may also be had with the same process and the same ingredients. For instance, 3 parts of alumi: num soap may be mixed with 3 parts of hydrocarbon-solvent to give a 50% solution."'To the gel formed by mixing the latter, I have found'by experiment that it is necessary to add .35 parts f of triethanolamine. in order to make the solution suificiently liquefied for application as a waterproofing material. And, various degrees or; con-' centration between these limits are obtained by similarly proportioning the ingredients.

After thus obtaining the stated result and in attempting to determine the theoretical basis of the reaction or reactions which changed the gel to a free-flowing liquid, I imagined that the triethanolamine added combined with some acid radical in the aluminum soap formed a soluble salt, because of the fact that triethanolamine is comparatively insoluble in the solvents used. To test out this theory, I dissolved triethanolamine stearate in the solvent and then to this solution added the correct proportions of aluminum soap and found that the aluminumsoap dissolved in the solution of solvent and triethanolamine stearate, although the same amount of aluminum soap in the same amount of solvent would have formed a gel had it not been for the presence of triethanolamine stearate, and this. unexpectedly confirmed my supposition that the triethanolamine combined with a small amount of free stearic or other free fatty acid in the aluminum soap in the first process above described.

From further experiments I determined that solutions of salts of alkyl or aryl amines, especially secondary or tertiary amines and substituted derivatives thereof, and especiallyhigh fatty acid salts of the mentioned group, such as triethanolamine stearate or diethylamine palmitate, will permit the solution of aluminum soaps to yield to get desired results.

Accordingly, it will be seen that the present invention in its more specific aspects, includes two methods of making aluminum soap solutions, the one first above described where a gel is formed and then liquefied, and the other which consists of dissolving triethanolamine stearate or any of the above enumerated fatty acid salts with gasoline, benzole, toluol, or other hydrocarbon-solvents and then dissolving in this solution the de-, sired amount of aluminum soap depending upon the degree of concentration desired. Of course, if high concentrations are desired, a greater relative quantity of triethanolamine stearate, or other alkyl amine or salt thereof, is dissolved in the solvent.

This method is more preferable than the first method described above wherein the gel is formed with the aluminum soap and solvent because it reduces the'cos't of manufacture. Yet, the first process described above forms part of the present invention and claims specific thereto will be presented in another application.

The ability to make highly concentrated aluminum soap solutions, which is taught by this invention, is a particularly important and advantageous feature in the art, for, in addition to the use of the concentrated solution as such, the latter may be diluted to the desired degree of con.-

centration by the addition to the solution of a further quantity of solvent. And, further, this additional quantity of solvent may be of a cheaper kind, thus effecting an economy in the production of solutions having relatively low degrees of nated articles of manufacture. both stone and fabric, with this solution, I deem as my invention not only the aluminum soap solution and process of making the same, but also articles of manufacture which are made impervious to moisture by the application of my waterproofing solution to the surface or into the pores thereof.

What I regard as new, and desire to secure by 4. An aluminumv soap solution including aluminimum soap, a hydrocarbon solvent, and an ethanolamine.

5. In the process of making an aluminum soap solution, the step which consists in including in the ingredients which comprise aluminum soap and a hydrocarbon solvent therefor, a quantity of triethanolamine.

6. In the process of making an aluminum soap solution, the step which consists in including in the ingredients which comprise aluminum soap and a hydrocarbon solvent therefor, a salt of an ethanolamine and a fatty acid of high molecular weight.

'7. In the process of making an aluminum soap solution, the step which consists in including in the ingredients which comprise aluminum soap and a hydrocarbon solvent therefor, a quantity of triethanolamine stearate.

8. In the process of making an aluminum soap solution having a hydrocarbon as the solvent, the step which consists in wetting the particles of aluminum soap with a salt of an ethanolamine and a fatty acid of high molecular, weight.

9. In'the process of making an aluminum soap solution having a hydrocarbon as the solvent, the step which'consists' inlwetting the particles of aluminum soap with triethanolamine.

10. In the process of making an aluminum soap solution having a hydrocarbon as the solvent, the step which consists in wetting the particles of aluminum soap with salts of ethanolamines with fatty acids of high molecular weight.

11. In the process of making an aluminum soap solution having a hydrocarbon as the solvent, the step which consists in wetting the particles of aluminum soap with an ethanolamine.

12. In the process of making an aluminum soap solution having a hydrocarbon as the solvent, the step which consists in adding salts or ethanolamines with fatty acids of high molecular weight to the solvent for the aluminum soap.

13. In the process of making aluminum soap solutions having hydrocarbon as the solvent and of desired degree of concentration which consists in making a relatively highly concentrated solution by mixing aluminum soap, a solvent therefor, and triethanolarnine; and then adding to the, solution a sufficient quantity of solvent to dilute the solution to the desired degree of concentration.

14. An aluminum soap solution including aluminum soap; a hydrocarbon solvent; and a substance selected from the group consisting of ethanoiamine and a salt of ethanolamine with fatty acids of high molecular weight.

JACOB DOIID. 

